JPH0399125A - Cooking utensil - Google Patents

Abstract

PURPOSE:To indicate clearly the temperature of a heater in a visual sense, increase the brightness of a cooking chamber and clean smoke and stain resultant from cooking by providing a smoke cleaning means based on a catalytic member which uses a flat-shaped silica tube heater and an inorganic fiber porous member and a stain cleaning means based on a coating film. CONSTITUTION:A plurality of heater lines 2 are arranged to run through a flat-shaped silica tube 1 for a cooking utensil, thereby forming a flat-shaped silica tube heater. A reflecting plate 9 is installed near the heater. Furthermore, a catalyzer 3 for smoke treatment is laid out so that an exhaust inlet 4, an exhaust passage 5 and an exhaust outlet 6 may be provided. In addition, an attempt is made to form a film for thermal decomposition of oil stain in an interior 7 of a cooking chamber so that the film may work by the heating operation of a heater 2 or a heater 8 installed on the bottom. After cooling, electric power is supplied to the silica tube heater 2 or the heater 8 for about two hours, which makes it possible to crack oil stain adhering to the interior of the cooking chamber and hence prevents smoke leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a cooking appliance equipped with a planar quartz tube heater, smoke treatment means, and means for thermally decomposing dirt.

PRIOR TECHNOLOGY No conventional cooking appliance has been found that is equipped with a smoke treatment means and a dirt thermal decomposition means, and whose heater is a flat quartz tube heater. In the prior art, the basic structure of the smoke treatment means is to disassemble oil smoke by installing a honeycomb carrying a catalyst in the exhaust passage of the cooking appliance, and there is no catalyst body other than the honeycomb. In addition, as a means for thermally decomposing dirt, a heat-resistant enamel coating is provided on the wall surface of the cooking chamber to reduce the temperature of the cooking chamber to about 45%.
One method is to raise the temperature to 0°C to decompose dirt, and the other is to provide a porous film containing a catalyst on the inner wall of the cooking chamber to decompose dirt using catalytic action at a lower temperature than in the case of enamel.

Furthermore, heaters include rod-shaped quartz tube type heaters, sheathed heaters, and flat heaters in which heating wire is wound around an insulating flat plate. Problems to be Solved by the Invention However, the above conventional technology has the following problems. In smoke treatment using honeycomb, a high layer height cannot be achieved due to pressure loss issues. Alternatively, the processing capacity is low due to the inability to increase the number of cells, and a high temperature is required to completely decompose the smoke, and a dedicated heater must be provided.

In addition, for thermal decomposition of dirt, the use of an enamel coating requires a large heater capacity, which is difficult to handle at 100V in Japan.Furthermore, enamel is susceptible to heat shock and may cause cracking and peeling. On the other hand, in the case of a porous film containing a catalyst, the film has weak strength and is easily scratched, and decomposition residues tend to remain inside the pores.

Next, in the case of a rod-shaped heater, the cooked food tends to be unevenly cooked, the heater area is small and the amount of heat is insufficient for raising the temperature of a large cooking chamber, and in the case of a flat heater,
There are cases where you cannot see the red-hot state of the heater and cannot get a visual image of the cooking process. The present invention solves the above-mentioned problems of the prior art, and provides a cooker that has a higher smoke processing ability and dirt decomposition ability than the conventional one, and can visually see red-hot bears at high temperatures. do. Means for Solving the Problems In order to solve the above problems, the present invention includes a planar quartz tube heater having at least two heater wires, and an inorganic fiber porous body containing an oxidation catalyst arranged near the heater. The cooking appliance is equipped with a means for treating smoke, and a means for forming a film having the ability to decompose and remove dirt on the wall surface of the cooking chamber, and thermally decomposing oil dirt and the like on this film.

action Hereinafter, the effects of the present invention will be explained.

First, let's explain about the heater. For heaters, avoid using flat quartz tubes and two or more heater wires. By making the quartz tube flat, it is possible to increase the heating area. It is clear that the temperature distribution of the quartz tube is high near the heater and becomes lower as it moves away from the heater. However, is the quartz tube one piece? Therefore, the red-hot state inside the cooking chamber is emphasized, which brings a great visual benefit. Furthermore, the temperature rise of the heater is faster than that of conventional planar heaters, and it is superior to conventional flat heaters in that it has a wide area and heats up quickly.

Next, we will explain the smoke processing means. The oxidation catalyst used in the present invention is Fe, Mn, Cu, Co, N
Transition metal oxides (including composite oxides) such as i, PL,
It can be made of any noble metal such as Pd. These oxidation catalysts are commercially available as Sio. -A
It is contained in a powdered state in a nonwoven fabric such as lzOs fiber. S
iO■-AI20. The fibrous nonwoven fabric has a porosity of 50 to 80% on average (pore diameters ranging from several 10 to several 100 μm) and easily captures smoke (oil smoke, etc.) with a particle size of approximately 0.1 to 10 μm. When the smoke is captured, oxygen from the air is easily supplied to the surface of the oxidation catalyst due to the structure of the non-woven fabric, and since it is placed near the heater and an appropriate temperature is obtained, the smoke is decomposed by the oxidation reaction. be done. From the above, the inorganic fiber porous material (nonwoven fabric) used for smoke treatment is particularly suitable for Sin. It does not need to be Altos fiber nonwoven fabric, but Zr0, AlzOs,
Any commercially available nonwoven fabric or woven fabric with suitable pores and porosity, such as SiCh, SiC, metal, and glass, may be used. Furthermore, since the oxidation catalyst is used in powder form, it does not necessarily have to have a large surface area or be highly active, and the smoke treatment of the present invention can achieve high performance with a relatively simple structure. can. In this respect, the oxidation catalyst may be those listed in claim (4).

Next, thermal decomposition of oil stains, etc. will be explained.

Dirt such as oil that adheres to the walls of the cooking chamber during cooking has a rating of 300.
At temperatures above ℃, it turns into tar and firmly adheres to the inner wall. If the catalyst used in the above-mentioned smoke treatment (oxidation catalyst tensless fiber porous material) is used, it will be easily oxidized and decomposed and will not turn into tar, but the catalyst does not have enough strength to be applied to the walls of the cooking chamber.

In the present invention, one method is to form a coating containing either MoS2MoOs on the wall surface of the cooking chamber in order to weaken the adhesion strength after taring.

MoS2 and Moss have a layered structure, which makes the coating surface slippery. Due to its slipperiness, it is possible to easily peel off the tar that has been deposited on the coating in the form of a film. The amount of oil generated from cooking is 3
At 50 to 400°C, it turns into tar in about 10 to 20 minutes,
If the tar is left heated for 1 to 2 hours, it will peel off and return to the original surface of the cooking chamber. Another method is to form a film containing transition metal oxides such as Fe, Mn, Cu, Co, Ni, and Mo, and use the oxidizing action of these oxides to decompose the dirt under heat.

EXAMPLE An example of the present invention will be described below with reference to the drawings. FIG. 1 is a simplified cross-sectional view of one embodiment of the cooking device according to the invention. A plurality of heater wires 2 are passed through a planar quartz tube 1 to form a planar quartz tube heater. A reflector plate 9 is provided near this heater, and a catalyst body 3 for smoke treatment is arranged so as to further provide an exhaust port 4, an exhaust passage 5, and an exhaust outlet 6. A film of thermal decomposition of oil stains is formed on the inside surface 7 of the cooking chamber.
The coating is made to function by heating with the heater 8 or the heater 8 provided on the bottom side. In the figure, 10a is a door, 10 is a door glass, 19 is a support leg, 20 is a support plate for a catalyst, and 21 is an exterior of a cooking device.

Figure 2 shows a simple perspective view of the flat quartz tube heater in Figure 1. Further, FIG. 3 also shows a sectional view of a cooking device of another embodiment.

A plurality of heater wires 12 are placed inside the quartz tube 1l to form a planar quartz tube heater, but in this case, the quartz tube is constricted to avoid contact between the heater wires. Others are the same as in Figure 1, including a reflecting plate l6, a catalyst body l3, an inner surface 14, and a heater l5.
It becomes.

FIG. 4 is a simple exploded sectional view of the planar quartz tube heater in FIG. 3.

The number of heater wires in the quartz tube was three in both FIG. 1 and FIG. 3, and two or three heater wires were energized at the same time with a 100 V power source. You can use more than four if necessary. All that is required is to control the energization pattern.

Using the cooker shown in Figures 1 and 3, prepare approximately 200g of horse mackerel.
I roasted them one by one. During cooking, the red-hot state of the quartz tube heater was visible through the door glass 10l7, and the horse mackerel was grilled without smoke leaking out.

After cooking, by energizing the quartz tube heater and heaters 8 and 15 for about 2 hours, the oil stains on the inside of the cooking chamber could be broken down. or,
The smoke generated at this time did not leak out.

Below, we will explain the planar quartz tube heater, smoke treatment, and dirt pyrolysis.

First, regarding the planar quartz tube heater, in the present invention, the conventional pipe-shaped quartz tube is processed into a shape in which the holes are two-dimensionally expanded, as shown in FIGS. 2 and 4. In this case, multiple heater wires are inserted. This allows the area of the heating surface to be made as large as that of conventional flat heaters, which prevents staining of the reflector and at the same time makes it possible to visually see the red heat of the heater. Furthermore, since the temperature rise is as fast as that of the conventional quartz heater, the planar quartz tube heater according to the present invention was able to combine the advantages of the conventional thousand-sided heater and the quartz tube heater.

In addition, by preventing the reflector from becoming dirty, a high reflection efficiency can be maintained at all times, so that the initial temperature rise characteristics (for the entire cooking chamber) can be prevented from deteriorating.

Next, regarding smoke treatment, in this example, low-cost Sin. -AI. A nonwoven fabric of Ox fibers was used. Fe. O.・CuO-MnzO
A catalyst body was prepared by dispersing approximately 50wt% of s. It appears that the catalytic performance can be exhibited even when the amount of the oxidation catalyst is 10% or less. The thickness of the nonwoven fabric was approximately 1 mm. This catalyst body is
If the arrangement is as shown in Figure 3, the smoke during cooking will decompose when the temperature near the surface of the catalyst is approximately 350°C.
It was confirmed that decomposition can be done even at 300℃ when there are few smoke crabs. The temperature required for this smoke decomposition can be sufficiently obtained by providing a catalyst near the quartz tube heater as in the structure of the present invention, and the distance between the reflector 9 and the catalyst 3 in FIG. 1 is about 10 g. is preferable. If this distance is too long, the temperature of the catalyst will drop, making it impossible to purify the smoke. Moreover, if the distance is too short, pressure loss will occur with respect to the exhaust flow, which is not preferable. The above smoke treatment showed much higher performance than when using conventional honeycomb. The main reasons for this are as follows. In the case of honeycomb, since it is a sintered body, only the area near the surface is the site of reaction, and the porosity and pore diameter, which are thought to contribute to the reaction, are much smaller than those of inorganic fiber porous bodies, and as a result, smoke particles are captured and Oxygen supply capacity becomes smaller.

In order to compare the oxidation ability of the catalyst body of the present invention and the catalyst-supporting honeycomb (made of cordierite), flat test pieces of 5cI1 x 5CI1 were prepared, and each surface was coated with 0.5% of vegetable oil.
When the catalyst of the present invention oxidized and decomposed the salad oil within 5 minutes, the catalyst body of the present invention oxidized and decomposed the salad oil within 5 minutes. However, in the case of honeycomb, oxidative decomposition does not proceed35
More than 60 minutes was required at a temperature of 0″C or more.The catalyst supported on the honeycomb was a bellows power type L a@.
1C o 03 and Pd. Pd is La*. q C
ea. + C O Os support layer? It was carried from

L a6, w C eo. + C o Os is Sin
g Al■O, when dispersed in fibrous nonwoven fabric, 250°C
The salad oil was completely oxidized and decomposed in the oven.

As described above, Sift-AI. When an oxidation catalyst is decomposed into a porous body made of inorganic fibers such as 03 fiber nonwoven fabric, a highly active catalyst body can be obtained, and it is ideal for treating smoke such as oil smoke, which has been difficult to do in the past.

Next, the decomposition of dirt on the walls of the cooking chamber will be explained.

Most of the dirt is oil, and conventionally the dirt has been decomposed using either a porous catalytic film or thermal decomposition as described above.

When oil is heated, it curls and adheres firmly to walls, etc. In the example, MoS. Alternatively, MoO1 was mixed with polyborosiloxane, a heat-resistant binder, to form a paint, and then a film was formed. In addition to Moss and MOO3, the paints include enamel frit, AI. Os was added. The polyborosiloxane is a mixture of 20 parts by weight of MoS or MoOs, 20 parts by weight of enamel frit, and 100 parts by weight of polyborosiloxane that is hot at 600°C or higher. 0. 1
Two types of paints were prepared by mixing 0 parts by weight. The paint containing MoOa was designated as paint 1, and the paint containing MoOa was designated as paint 2. Paint 1 was baked at 450°C, and paint 2 was baked at 600''C to form a film of paint 1 in Fig. 1 and paint 2 in Fig. 3, respectively.After the surface of this film was stained by actual cooking, When the coating temperature was maintained at 350°C or higher for about 2 hours by heating with a heater, all cooking stains except salt and ash were removed.Also, the same coating was applied to SUS430 locm x 10cm (
After dropping 0.5 g of salad oil onto the test bead with a thickness of 0.5 + am) and leaving it in an oven at about 380°C, it turned into a hard film-like tar within 30 minutes, and after that, The tar gradually peeled off and was completely peeled off in about 2 hours. Similarly, glass plates, metal (SUS)
430) Plates, enameled iron plates, and conventional porous catalyst coatings were also subjected to salad oil decomposition tests, but tar remained attached to all but the porous catalyst coating, and even with porous coatings, the base material and coating It was found that tar remained as a residue at the interface or inside the pores. The porous catalyst film used here contains oxides of metals such as Mn, CU, and Fe, diatomaceous earth, zeolite, and alkaline earth oxides in an argonium phosphate binder. In addition, in terms of film strength, the pencil hardness of Paint 1 and Paint 2 is 9H or higher, and although it is more easily scratched than enamel, it is much harder and denser than a porous film. Further, even after 10 cycles of heat shock from 800° C. to water, there was no cracking or peeling, and strong adhesion was observed.

The coating of the present invention is applied to Mob., which is used as a lubricant.
Since similar results were obtained with MoO3, it was applied as the coatings shown in Figures 1 and 3. We also tried mixing other silicate compounds such as montmori kuchinite into the paint due to the common feature that the compounds are layered in structure, but we did not get favorable results when decomposing salad oil. However, this was also unsuitable for decomposing salad oil. Therefore, MoSz M0
0=Force {It can be seen that it is appropriate.

On the other hand, MOS2. Fe with oxidizing activity other than MO○
Coatings containing oxides of , Mn, Cu, Co, Ni, and Mo were also produced. The binder was polyborosiloxane, and to 100 parts by weight of the binder, 30 parts by weight of oxide, 20 parts by weight of hollow frit, and 10 parts by weight of AL20 were blended. Apply this on the StlS430 test piece for 60 minutes.
A film was formed by firing at 0°C. The oxide used was Fe2
0z ・Mnz 03 ・Cu○, NiO-MoO
i , CotOs ・Mnz o3 ・cuO,
Cent H CuXMns-x Oa (0<x<
1.5). As a dirt decomposition test, 0.5g of salad oil was dropped onto the test piece film at 350"C, 38
When left in an open air at 0°C and 400'C, 38% (decomposed in 2 to 3 hours at 1°C, but at 350'C
I couldn't disassemble it. This result shows that films containing transition metal oxides can also be applied to the present invention.

In addition to polyporosiloxane, the binder has a structure of WIi.
91 polytitanoloposilane may also be used.

In the case of polytitanocarbosilane, a glossier coating can often be obtained than polyborosiloxane.

Effects of the Invention As explained above, the cooking appliance of the present invention is equipped with an unprecedented planar quartz tube heater, smoke purification means using a catalyst body using an inorganic fiber porous body, and MO32 or MoO
(1) When cooking using a heater, you can visually feel the warmth of the heater, and the brightness inside the cooking chamber is also brighter than before. be able to.

(2) Clean cooking is possible because smoke and dirt from cooking can be purified.

[Brief Description of the Drawings] Fig. 1 is a schematic cross-sectional view of a cooking device according to an embodiment of the present invention, and Fig. 2 is a schematic exploded cross-sectional view of a flat quartz tube heater used in the cooking device of Fig. 1. , FIG. 3 is a schematic sectional view of a cooking device of another embodiment, and FIG. 4 is a schematic exploded sectional view of a planar quartz tube heater used in the cooking device of FIG. 3. DESCRIPTION OF SYMBOLS 1... Planar quartz tube, 2... Heater wire, 3... Catalyst body, 5... Wandering passage, 7
...Inner surface of the cooking chamber with film formed, loa...
··door.

Claims (5)

[Claims] (1) A cooking chamber for heating food, a translucent door through which the inside of the cooking chamber can be seen, a heater for heating food, a smoke disposal means generated during cooking, and a cooking chamber. The heater is a planar quartz tube heater having at least two heater wires, and the smoke processing means is a means for thermally decomposing dirt such as oil adhering to the indoor wall. A catalyst body made of a porous inorganic fiber in which an oxidation catalyst is dispersed is provided at a certain distance from the heater, and a space at a certain distance between the heater and the catalyst body is used as an exhaust passage to remove the dirt. The thermal decomposition means is a cooking appliance in which a coating having the ability to decompose and remove dirt is formed on the inside of the cooking chamber. (2) The coating that has the ability to decompose and remove dirt uses polyborosiloxane or polyborotitanocarbosilane as a binder, and at least MoS_2 or Mo
The cooking device according to claim 1, wherein a filler containing any one of O_3 as a main component is dispersed. (3) A film that has the ability to decompose and remove dirt, using polyborosiloxane or polytitanocarbosilane as a binder, and dispersing at least one or more oxides of Mn, Cu, Co, Ni, and Mo. The cooking device according to claim (1). (4) The cooking device according to claim (1), wherein the oxidation catalyst is one or more of the following: an oxide or composite oxide of a transition metal, a composite oxide of a transition metal and another element, a platinum group element, or a transition metal. (5) The porous body of inorganic fiber is SiO_2-Al_2O_
3 fiber, SiO_2 fiber, glass fiber, metal fiber, Al
The cooking appliance according to claim (1), which is a nonwoven fabric or a woven fabric of any one of _2O_3 fiber, ZrO_2 fiber, and SiC fiber.